Calling device for telephone-exchanges.



No. 870,634. PATENTED NOV. 12, 1907.

F. A. LUNDQUIST. I CALLING DEVICE FOR TELEPHONE EXCHANGES.

APPLIOATION FILED MAY 28. 1906.

3 SHEETS-SHEET 1.

- fire/Mo @CWJ WQ'J No 870,634. PATENTED NOV. 12, 1907.

F. A. LUNDQUIST.

CALLING DEVICE FOR TELEPHONE EXCHANGES.

APPLIOATION FILED MAY 26. 1906.

3 SHEETS-:SHEET 2.

Ii. I

F. A. LUNDQUIST.

CALLING DEVICE FOR TELEPHONE EXCHANGES.

I nrmourmn FILED MAY 2a. 1906.

PATENTED NOV. 12, 1907.

8 SHEETS-SHEET 8.

FRANK A. LUNDQUIST, OF CHICAGO, ILLINOIS CALLING DEVICE FOR TELEPHONE-EXCHANGES.

Specification of Letters Patent.

Patented Nov. 12, 1907.

' Application fil d May 28.1906. Serial No. 319.065.

To all whom it may concern: I

Be it known that I, FRANK A. LUNDQUIST, a citizen of the United States of America, and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Calling Devices for Telephone-Exchanges, of which the following is'a specification.

Myinvention relates to calling devices for telephone exchanges, and has for its object improvements in such devices.

In the accompanying drawings Figure 1 is a front elevation; Fig. 2 is a rear elevation; Fig. 3 is a view partly broken awayin the direction of the arrow'3 of Fig. 2; Fig.2 is a section on line 44 of Fig. 3; Figs. 5 and 6 are partial views similar to Fig 3 showing some of the operating parts in different positions. Fig. 7 is a partial section on 7--7 of Fig. 4 at the time of making contact between the part in section and the contact spring it engages; Fig.3 is a partial section on line 88 of Fig. 4; and Fig. 9 is a detached view of the lever by whichthe device is operated.

In the said drawings A is a dial plate having a series of numbers or characters on a portion A adjacent to one part 'of its face. In said dial plate is a slot A havinglateral extensions toward the indicating characters A, and terminating in a large opening A. Secured to the back of'the dial A, by suitable posts, is a clock mechanism B provided with a motor springB and a governor B for preventing too rapid movement. A ratchet and pawl mechanism B serves to cause the governor B to be'driven by the spring B only during the return to normal movement, which movement is that in which the actuating electrical contacts are made by the calling device.

Secured to'the center post 0, on which the spring B ismounted, is a plate 0 provided with lips 0 between which lips ispivoted an arm on lever D. The arm D normally projects up through the slot A -A and its free end terminates 'in an inclined finger-hold head D which normally rests in the position shown in Figs. 1 and 3. By taking hold of the projecting part D and moving toward the left past the laterally projecting openings A the plate 0 is rotated and the spring B is wound up. By observing Fig. 3 it will be seen that the projecting part D, which the operator takes hold of with his finger, is above the pivoting point of the arm D. Pressure on the finger piece D to move it to the left, as shown in Fig. 1, will therefore act to turn thelever D outward on its pivot. Such outward movement is, however,-prevented by the lever itself engaging the inner. face of the dial A.

Insulatingly secured to the plate 0 is atoothed sector 0 one portion 0 of which is bent downward as shown in Figs. 3 and 7. Insulatingly secured at some convenient part of the framework of the device are two contact springs E and E, one of which is adapted trical engagement.

to he engaged by the teeth of the sector 0 and the other bythe projection C. Electrically connected to the sector 0 is a spring 0", the free end of which engages -a piece of insulation D on the arm D. Secured to the plate C directly back of or beneath the spring C is an insulated contact point C.

When the linger piece D is' above or in front of the dial plate or disk A, the arm 'holdsthe spring C away from contact with the point C, but when the finger piece is behind the dial, C and C arein elec- The device is provided with three electrical connections, the springs E and E being connected to the two metallic limbs, on an operating circuit,- and the contact point C to a battery wire. When the spring C is in' engagcmentwith the contact point C, each contact between the sector C and the spring E sends an impulse from the battery over one line limb and ground return, while a contact between the projection C and spring E sends an impulse over the other line limb and ground return. When the spring C is separated from the battery terminal 0, contacts with E and E are'non-effective. Inaddition to these there are two springs, 15 and 16, which are held in electrical connection with each other by an arm C when the mechanism is in its normal position. When the arm Dis moved the movement of the spindle C carries the arm C away and permits the springs 15 and 16 to separate. These springs are in the receiver circuit and the opening of them prevents a battery current reaching the receiver during the operation of the calling device.

The-device is intended forthe use of subscribers at the local stations of an automatic telephone exchange, and is particularly adaptedto calling station numbers consisting of two or more figures. Assuming that the first figure of the number to be called is 7 'the subscriber places his finger against the upper projecting part of the lever D adjacent to the inclined plate D,

, and moves the lever around until the lower edge of the inclined part D is over the lateral slot A that is opposite the figure 7 on the indicator A. By then pressing the lever down the inclined part will pass through this lateral slot and the entire part engaged by the finger (the inclined ,part D and the extreme upper projecting part of the lever or arm B) will pass behind the dial A so as to be completely out of the reach of the operator. In fact, it is not really necessary to push the inclined part D down through a slot A as that result will automatically be accomplished by merely removing the finger from the part D. This will be evident from the fact that the finger pressureon the extreme upper end of the lever D necessary to overcome the comparatively strong resistance of the spring B, acts to hold the inclined part D outside of the dial plate A, but as soon as that pressure is removed the comparatively weak spring C serves to move the level D inward so that theinner edge of the inclined part D will pass into the nearest transverse slot A 'As soon as this occurs, the action of the spring B in returning the mo'vedparts to normal position, brings the inclined part 1:) against the metal forming the boundary of the slot Ai'and forces the finger part back of the dial plate irrespective of the operator or the spring C As soon as thelever is completely behind the dial plate A the. spring Ch -engages the contact point C and com,-

pletes electrical connection from the battery to the sec;

tor C This position is shown in Fig. 5.

The sector 0? is so located with respect to the arm or.

lever D that when the inclined part D passes through a slot A having any particular adjacent number, the said sector, in returningto normal position, will make as many electrical connections with the spring E as was indicated by that number. Thus, after D passes down through slot number 7 and the spring C 'engages the contact point 0 the sector will' make seven contacts withispring to send seven impulses overthe line connected thereto. I

Immediately after the projection C makes contact with thespring E the inner edge of the inclined part D comes into contact with an inwardly inclined piece A which may conveniently be a part of the metal cut out to form the opening A in the dial plate A. The

superior force of the motor springB over the contact spring Ciforces the free end of the lever D up to. the incline A (Fig. 6) until said lever finally rests in nor-. inal position as shown in Figs. 1 and 3;. The subscriber therein. As soon as this is done and the leverreleased,

the operation is completely automatic and entirely within the device and cannot be interfered with except by the use of some special tool or appliance.

What I claim is:- p 1. In a calling device, a series of indicating characters mounted upon a plate, a lever adapted to be moved by in the device and outof reach of the operator, and means by which upon said lever passing withinthe device said device will automatically make a series of electrical contacts corresponding in number to the indication to wh-ich the lever was moved by hand.

2. The combination with a dial plate provided with numbers and having openings adjacent to .its numbers, of a lever adapted to be manually moved'to engage any one of said openings, acontact making device arranged to be set by such movement of saidlever, and automatically operating means by-which upon releasing. said'lever, it will pass behind said plate so as to be out ofthe reach of mam ual operation and said contact maker will make as many contacts as was primarilyiindicated by the manual operation of said lever.

3; The combination wlth'a calling device arranged to make a series of electrical contacts corresponding to a manual operation thereof, of a lever by which ,the device is set for any'desired number of contacts to be made, and

automatically operating means by which upon releasing ,said' lever it will pass within the device and remain there FRANK A. LUNDQ'UIST.

Witnesses N.,E. Nons'rnom, C L, Rsmrrnnn. 

